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Dielectrophoretic stretching of DNA tethered to a fiber tip.

ABSTRACT: In this work, we studied the stretching of ? phage DNA molecules immobilized on an optical fiber tip attached to a force sensitive tuning fork under ac electric fields. We designed a two electrodes stretching system in a small chamber: one is a gold-coated optical fiber tip electrode, and the other is a gold-coated flat electrode. By applying a dielectrophoretic (DEP) force, the immobilized ? DNA molecules on the tip are stretched and the stretching process is monitored by a fluorescent microscope. The DNA stretching in three-dimensional space is optimized by varying electrode shape, electrode gap distance, ac frequency, and solution conductivity. By observing the vibrational amplitude change of a quartz tuning fork, we measured the effects due to Joule heating and the DEP force on the tethered DNA molecules in solution. This work demonstrates a method to manipulate and characterize immobilized ? DNA molecules on a probe tip for further study of single DNA molecules.

SUBMITTER: Hyun C

PROVIDER: S-EPMC4411638 | biostudies-literature | 2015 Mar

REPOSITORIES: biostudies-literature

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Dielectrophoretic stretching of DNA tethered to a fiber tip.

Hyun Changbae C Kaur Harpreet H McNabb David S DS Li Jiali J

Nanotechnology 20150305 12

In this work, we studied the stretching of λ phage DNA molecules immobilized on an optical fiber tip attached to a force sensitive tuning fork under ac electric fields. We designed a two electrodes stretching system in a small chamber: one is a gold-coated optical fiber tip electrode, and the other is a gold-coated flat electrode. By applying a dielectrophoretic (DEP) force, the immobilized λ DNA molecules on the tip are stretched and the stretching process is monitored by a fluorescent microsco ...[more]

PMID: 25741602

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